Magnetic tape drive for a single-reel type magnetic tape cartridge

ABSTRACT

In a magnetic tape drive for a single-reel type magnetic tape cartridge having a leader block coupled to a leading end of a magnetic tape wound therein, a hub for winding the tape pulled out of the cartridge is disposed at rear side of a magnetic head unit for writing data on and reading data from the tape, and has a radial slot formed therein for receiving the leader block of the tape threaded through the unit. The rotational direction of the hub is determined such that the leader block is subjected to an radially-inward force in the slot of the hub at the beginning of a rotational movement of the hub, whereby slippage of the leader block from the slot of the hub can be prevented. A flat flexible printed-circuit cable is used in the drive to establish an electrical connection between a magnetic head of the unit and an amplifier printed-circuit board thereof, and includes a flexible plate having circuit patterns formed on the side faces thereof and connected to each other by through-holes formed therein, and connectors provided on the side faces of the plate and disposed at the ends thereof. The plate is symmetrically shaped with respect to a geometrical center thereof, and the connectors are symmetrically disposed thereto.

This application is a continuation of application Ser. No. 08/303,029filed on Sep. 8, 1994 now abandoned.

1) Field of the Invention

The present invention relates to a magnetic tape drive, for asingle-reel type magnetic tape cartridge, which is used as an externalmemory device of an computer, and more particularly to improvements tosuch a magnetic tape drive. The present invention also relates to aflexible printed-circuit cable used in the magnetic tape drive toconnect a magnetic head to an amplifier control printed-circuit boardtherefor.

2) Description of the Related Art

A magnetic tape drive for a single-reel type magnetic tape cartridge isdisclosed in, for example, Japanese Unexamined Japanese PatentPublications No. 3-105758 and No. 3-272046. In this field, there is ademand for a magnetic tape drive, as mentioned above, that is as compactas possible and it is also required that the number of the parts in themagnetic tape drive are reduced as much as possible. There remains roomfor improvements in the compactness of such a magnetic tape drive.

SUMMARY OF THE INVENTION

Accordingly, an object of the present invention is to provide a magnetictape drive for a single-reel type magnetic tape cartridge directed toreducing the number of parts used therein and to making the entire drivemore compact.

Another object of the present invention is to provide a flexibleprinted-circuit cable for use in the magnetic tape drive to connect amagnetic head to an amplifier control printed-circuit board therefor,which can be used to make the magnetic tape drive more compact asmentioned above.

In accordance with an aspect of the present invention, there is provideda magnetic tape drive for a single-reel type magnetic tape cartridge,the cartridge having a leader block coupled to a leading end of amagnetic tape wound up therein, the drive comprising a magnetic headunit for writing data on and reading data from the magnetic tape, and ahub member disposed at the rear of the magnetic head unit and having aradial slot formed therein for receiving the leader block of themagnetic tape threaded through the magnetic head unit, wherein therotational direction of the hub member is determined such that theleader block is subjected to an radially-inward force in the radial slotof the hub member at the beginning of a rotational movement of the hubmember, whereby slippage of the leader block from the radial slot of thehub member can be prevented.

In accordance with another aspect to the present invention, there isprovided a magnetic tape drive for a single-reel type magnetic tapecartridge having a leader block coupled to a leading end of a magnetictape wound up therein, the drive comprising a magnetic head unit forwriting data on and reading data from the magnetic tape, a hub memberdisposed at a rear side of the magnetic head unit and having a radialslot formed therein for receiving the leader block of the magnetic tapethreaded through the magnetic head unit, a data write amplifierprinted-circuit board and a data read amplifier printed-circuit boardprovided below the magnetic head and connected to the the magnetic headof the unit, and at least two flat flexible printed-circuit cablespartially disposed between the magnetic head unit and the hub member toestablish an electrical connection between the magnetic head of the unitand the amplifier printed-circuit boards, wherein each of the flatflexible printed-circuit cables includes a flexible plate element, andconnector elements provided on the side faces of the flexible plateelement and disposed at the ends thereof, the flexible plate elementhaving a circuit pattern for connecting the connector elements to eachother.

In accordance with yet another aspect of the present invention, there isprovided a flat flexible printed-circuit cable to be used in a magnetictape drive for driving a single-reel type magnetic tape cartridge, toestablish an electrical connection between a magnetic head and anamplifier printed-circuit board thereof, comprising: a flexible plateelement having circuit patterns formed on the side faces thereof andconnected to each other by through-holes formed therein; and connectorelements provided on the side faces of the flexible plate element anddisposed at the ends thereof, the connector elements being connected toeach other by the circuit patterns. Preferably, the flexible plateelement is symmetrically shaped with respect to a geometrical centerthereof, and the connector elements are symmetrically disposed withrespect to the geometrical center of the flexible plate element.

BRIEF DESCRIPTION OF THE DRAWINGS

The other objects and advantages of the present invention will be betterunderstood from the following description, with reference to theaccompanying drawings, in which:

FIG. 1 is a perspective view showing the appearance of a magnetic tapedrive according to the present invention;

FIG. 2 is a perspective view showing a single-reel type magnetic tapecartridge to be used in the magnetic tape of FIG. 1;

FIG. 3 is a perspective view, similar to FIG. 1, wherein a cover hasbeen removed from the magnetic tape drive shown therein;

FIG. 4 is a perspective view, similar to FIG. 3, wherein a controlprinted-circuit board has been removed from the magnetic tape driveshown therein;

FIG. 5 is a perspective view, similar to FIG. 4, wherein a guide plateof a threader assembly has been removed from the magnetic tape driveshown therein;

FIG. 6 is a plan view showing the arrangement of the elements necessaryfor threading a magnetic tape pulled out of the single-reel typemagnetic tape cartridge;

FIG. 7 is a plan view, similar to FIG. 6, in which the threading of themagnetic tape is finished;

FIG. 8 is a partially-enlarged view of FIG. 7;

FIG. 9 is a plan view showing a conventional arrangement correspondingto that of FIG. 7;

FIG. 10 is an partially-enlarged view of FIG. 9, corresponding to FIG.8;

FIG. 11 is a perspective view showing a unit including a magnetic headassembly and a pair of guide rollers mounted on a plate-like basemember;

FIG. 12 is a partial cross-sectional view taken along the line XII--XIIof FIG. 5; and in the direction indicated generally;

FIG. 13 is a plane view showing an arrangement of a readout amplifierprinted-circuit board, a writing amplifier printed-circuit board, andflat flexible printed-circuit cables for connecting a magnetic head tothe printed-circuit boards;

FIG. 14 is a perspective view showing conventional flat flexibleprinted-circuit cables;

FIG. 15 is a perspective view showing a magnetic head unit in which theflat flexible printed-circuit cables of FIG. 14 are used;

FIG. 16 is a plan view showing a preferable form of a flat flexibleprinted-circuit cable according to the present invention;

FIG. 17 is a plan view showing the rear side of the flat flexibleprinted-circuit cable of FIG. 16;

FIG. 18 is a side view observed along a line XVIII--XVIII of FIG. 16;and in the direction indicated generally;

FIG. 19 is a plan view showing a flat flexible printed-circuit cable;

FIG. 20 is a plan view showing the flat flexible printed-circuit cableof FIG. 19 rotated by an angle of 90 degrees;

FIG. 21 is a plan view showing the flat flexible printed-circuit cableof FIG. 20 rotated by an angle of 90 degrees; and

FIG. 22 is a plan view showing the flat flexible printed-circuit cableof FIG. 21 rotated by an angle of 180 degrees.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1 shows the appearance of a magnetic tape drive, generallyindicated by reference numeral 10, which comprises a main frame 12, acover 14 detachably attached to the main frame 12, and a front controlpanel 16 attached to a front side of the main frame 12. The controlpanel 16 is provided with operating keys 16a, and a liquid crystaldisplay 16b associated therewith. Also, the control panel 16 has aninlet port 16c formed therein to allow insertion of a single-reel typemagnetic tape cartridge into the magnetic tape drive 10.

FIG. 2 shows the single-reel type magnetic tape cartridge, generallyindicated by reference numeral 18, which comprises a rectangular case18a having a hub (not visible) rotatably provided therein, and amagnetic tape 18b is wound around the hub. As shown in FIG. 2, theleading end of the magnetic tape 18b is securely coupled to a leaderblock 18c by a plug-like element 18d which may be formed of a hardrubber material. Namely, the coupling of the leading end of the magnetictape 18b to the leader block 18c is carried out by forcibly insertingthe plug-like element 18d together with the leading end of the magnetictape 18b into a hole 18e formed in the leader block 18c. As is obviousfrom FIG. 2, a side wall of the hole 18e is opened, and the magnetictape 18b is extended from the opened side wall of the hole 18e.

In FIG. 3, the cover 14 is removed from the magnetic tape drive 10 shownin FIG. 1, and a main control printed-circuit board 20 for controllingthe operation of the drive 10 is shown attached to column elements 12awhich forms a part of the main frame 12. Also, in FIG. 3, a loaderassembly 22, for moving the single-reel type magnetic tape cartridge 20to an operational position, is partially visible.

In FIG. 4, the main control printed-circuit board 20 is removed from themagnetic tape drive 10 shown in FIG. 3, and a threader assembly 24 forthreading the magnetic tape 20b along a given magnetic tape path isvisible. The threader assembly 24 includes a guide plate 24a supportedby the column elements 12a of the main frame 12, and the guide plate 24ahas a guide slot 24b formed therein which extends along with saidmagnetic tape path. The threader assembly 24 also includes a link/armmechanism (not visible) provided on a lower side of the guide plate 24a,and the link/arm mechanism has a pin element 24c attached to an end ofan arm element thereof. The pin element 24c is slidably received in theguide slot 24b, and is engageable in a recess 18f (FIG. 2) formed in thefree end of the leader block 18c.

In FIG. 5, the guide plate 24a of the threader assembly 24 is removedfrom the magnetic tape drive 10 shown in FIG. 4, and an electric motor24d forming a part of the threader assembly 24 is visible. The link/armmechanism of the threader assembly 24 is driven by the motor 24d suchthat the pin element 24c is moved along the guide slot 24b of the guideplate 24a. Also, in FIG. 5, a magnetic head assembly 26, a pair of guiderollers 28a and 28b provided on sides thereof, and an additional guideroller 30 provided beside the guide roller 28b are visible, and theseelements partially define the above-mentioned magnetic tape path.Further, a hub 32 is visible, and the hub 32 is provided between theloader assembly 22 and the magnetic head assembly 26. The hub 32 has aradial slot 32a formed therein, and the radial slot 32a is sized so asto fitly receive the leader block 18c.

When the single-reel type magnetic reel cartridge 18 is loaded in themagnetic tape drive 10, and when the pin element 24c is brought to theend of the guide slot 24b by the link/arm mechanism of the threaderassembly 24, as shown in FIG. 4, the pin element 24c can be engaged inthe recess 18f of the leader block 18c. Then, the leader block 18c ismoved along the guide slot 24b by the link/arm mechanism of the threaderassembly 24, so that the magnetic tape 18b is pulled out of the magnetictape cartridge 18, as shown in FIG. 6. The movement of the leader block18c along the guide slot 24b continues until the leader block 18c isinserted into the radial slot 32a of the hub 32, so that the magnetictape 18b is threaded around the guide roller 28a, over the magnetic headassembly 26, and around the guide rollers 28b and 30, as shown in FIG.7. After the leader block 18c is inserted into the radial slot 32a ofthe hub 32, the pin element 24c is disengaged from the recess 18f of theleader block 18c, and then the hub 32 is rotated in a direction asindicated by an arrow A in FIG. 8, to write data on the magnetic tape18b or to read data from the magnetic tape 18b.

The rotational direction of the hub 32 as indicated by the arrow A issignificant because slippage of the leader block 18c from the radialslot 32a of the hub 32 can be effectively prevented at the beginning ofthe rotational movement of the hub 32, due to the fact that the leaderblock 18c is subjected to a radially-inward force as indicated by anarrow B in FIG. 8, which is derived from a tightening force exerted onthe magnetic tape 18b.

FIG. 9 shows a conventional arrangement corresponding to that of FIG. 7,and the elements similar to those of FIG. 7 are indicated by likereferences primed. In the conventional arrangement, the threading of amagnetic tape 18b' and the insert of a leader block 18c' can be carriedout in the same manner as mentioned above, but a hub 32' is rotated inthe reverse direction as indicated by an arrow A' in FIG. 10corresponding to FIG. 8. In this case, slippage of the leader block 18c'from a radial slot 32a' of the hub 32' cannot be prevented at thebeginning of the rotational movement of the hub 32', because the leaderblock 18c' is subjected to a radially-outward force as indicated by anarrow B' in FIG. 10, which is derived from an tightening force exertedon the magnetic tape 18b'. Thus, the hub 32' must have a means forpreventing the slippage of the leader block 18c' from the radial slot32a' of the hub 32'. In the example shown in FIGS. 9 and 10, the hub 32'has a leaf spring element 32b' incorporated therein, as theslippage-preventing means, and the leaf spring element 32b' isengageable with the leader block 18c' upon inserting it into the radialslot 32a' of the hub 32'. of course, according to the present invention,with the arrangement as shown in FIGS. 7 and 8, no slippage-preventingmeans such as a leaf spring element is necessary, because the leaderblock 18c is subjected to a radially-inward force (arrow B) whichresults from the tightening force exerted on the magnetic tape 18b.

Note, in the embodiment shown in FIGS. 1 to 8, the hub 32 may beconstructed as a double-flanged hub for winding the magnetic tapeexactly therearound.

As best shown in FIG. 11, the magnetic head assembly 26 includes amagnetic head 26a, and a holder frame 26b for holding the magnetic head26a, and the holder frame 26b is provided with two guide faces 26cdisposed at the sides of the magnetic head 26a, for guiding the magnetictape 18b. The magnetic head assembly 26 and the guide rollers 28a and28b are mounted on a plate-like base member 34 as a unit, and the basemember 34 is securely attached to the main frame 12 by screws (notshown). As shown in FIGS. 12 and 13, the magnetic head 26a is connectedto a data write amplifier printed-circuit board 36 through flat flexibleprinted-circuit cables 40W₁ and 40W₂ for writing data from the magnetictape, and is also connected to a data read amplifier printed circuitboard 38 through flat flexible printed-circuit cables 40R₁ and 40R₂ forreading data on the magnetic tape. As shown in FIG. 12, the amplifierprinted-circuit boards 36 and 38 are horizontally disposed above andbelow with respect to each other.

In particular, two small relay printed-circuit boards 42 and 44 arevertically attached to the base member 34, and are symmetricallydisposed with a horizontal central axis X passing through the middle ofthe magnetic head 26a. The relay board 42 has two female type connectors46W₁ and 46R₁ provided on a front side thereof, and the connectors 46W₁and 46R₁ are connected a given circuit pattern formed in the relay board42. Similarly, the relay board 44 has two female type connectors 46R₂and 46W₂ provided on a front side thereof, and the connectors 46R₂ and46W₂ are connected to a given circuit pattern formed in the relay board44. As shown in FIG. 13, two bundles of electric wires 48 and 50 areextended from the magnetic head 26a, and are connected to the circuitpatterns formed in the boards 42 and 44, respectively. On the otherhand, the data write amplifier board 36 has two female type connectors48W₁ and 48W₂ provided thereon and symmetrically disposed with thehorizontal central axis X passing through the middle of the magnetichead 26a, and the data read amplifier board 38 also has two female typeconnectors 50R₁ and 50R₂ provided thereon and symmetrically disposedwith the horizontal central axis X. The flat flexible cable 40W₁ has afirst male type connector 52W₁ provided on one side thereof and disposedat one end thereof, and a second male type connector 54W₁ provided onthe other side thereof and disposed at the other end thereof; the flatflexible cable 40W₂ has a first male type connector 56W₂ provided on oneside thereof and disposed at one end thereof, and a second male typeconnector 58W₂ provided on the other side thereof and disposed at theother end thereof; the flat flexible cable 40R₁ has a first male typeconnector 60R₁ provided on one side thereof and disposed at one endthereof, and a second male type connector 62R₁ provided on the otherside thereof and disposed at the other end thereof; and the flatflexible cable 40R₂ has a first male type connector 64R₂ provided on oneside thereof and disposed at one end thereof, and a second male typeconnector 66R₂ provided on the other side thereof and disposed at theother end thereof. As is obvious from FIGS. 11 and 13, the cable 40W₁ isbent at an angle of about 90 degrees, and the first and second male typeconnectors 52W₁ and 54W₁ thereof are coupled to the female typeconnectors 46W₁ and 48W₁ ; the cable 40W₂ is bent at an angle of about90 degrees, and the first and second male type connectors 56W₂ and 58W₂thereof are coupled to the female type connectors 46W₂ and 48W₂ ; thecable 40R₁ is bent at an angle of about 90 degrees, and the first andsecond male type connectors 60R₁ and 62R₁ thereof are coupled to thefemale type connectors 46R₁ and 50R₁ ; and the cable 40R₂ is bent at anangle of about 90 degrees, and the first and second male type connectors64R₂ and 66R₂ thereof are coupled to the female type connectors 46R₂ and50R₂. Thus, an electrical connection is established between the magnetichead 26a and the amplifier printed-circuit boards 36 and 38.

The arrangement of the flat flexible cables 40W₁, 40W₂, 40R₁, and 40R₂bent at the angle of about 90 degrees for establishing the electricalconnection between the magnetic head 26a and the amplifierprinted-circuit boards 36 and 38 is significant because the distancebetween the magnetic head assembly 26 and the hub 32 can be decreasedand thus the magnetic tape drive can be made more compact. Also, thearrangement of the amplifier printed-circuit boards 36 and 38 disposedabove and below with respect to each other is significant because aheight of the magnetic tape drive 10 can be decreased.

FIG. 14 shows conventional flat flexible printed-circuit cables 68 usedin an magnetic tape drive. Each of the flat flexible cables 68 has maletype connecters 70 provided at the ends thereof, and is folded atsuitable locations thereof in use, as shown in FIG. 15. In FIG. 15, amagnetic head unit 72 includes a semi-circular-shaped tape guide member72a, and a magnetic head assembly 72b incorporated in the guide member72a, and the magnetic head assembly has two relay printed-circuit boards72c associated therewith, which may be constituted in the same manner asthe above-mentioned relay printed-circuit boards 42 and 44. Each of theflat flexible cables 68 are folded and arranged to establish anelectrical connection between an magnetic head of the assembly 72b andamplifier printed-circuit boards (not shown). As is obvious from FIG.15, the conventional arrangement of the folded flat flexibleprinted-circuit cables 68 is very bulky, and does not allow the size ofthe magnetic tape drive to be reduced.

It should be noted that the rotational direction of the hub 32 asindicated by the arrow A (FIG. 8) is made possible by using the flatflexible printed-circuit cables 40W₁, 40W₂, 40R₁, and 40R₂, without anybulkiness of the magnetic tape drive 10. Namely, this is because theflat flexible printed-circuit cables 40W₁, 40W₂, 40R₁, and 40R₂ can becompactly arranged even though the space between the magnetic headassembly 26 and the hub 32 is restricted due to the existence of theadditional tape guide roller 30.

FIGS. 16, 17, and 18 shows a preferable form of the flat flexibleprinted-circuit cable (40W₁, 40W₂, 40R₁, and 40R₂), and this preferableflat flexible cable, generally indicated by reference numeral 40,comprises a flexible plate element 40a symmetrically shaped with respectto a geometrical center thereof and having respective circuit patterns40b and 40c formed on the side faces thereof. As illustrated in FIGS. 16and 17, each of the circuit patterns 40b and 40c includes a plurality offine conductive segments, the fine segments forming the pattern 40b areconnected to the fine segments forming the pattern 40c by through-holes40d formed in the flexible plate element 40a. Note that, of course, thepattern 40b, 40c is preferably covered by a protective layer. The flatflexible cable 40 also comprises a first male type connector 40e and asecond male type connector 40f provided on the side faces of theflexible plate element 40a and symmetrically disposed at the endsthereof with respect to the geometrical center, as shown in FIG. 18. Theconnector 40e is connected to the fine conductive segments forming thepattern 40b, and the connector 40f is connected to the fine conductivesegments forming the pattern 40c.

When the flat flexible printed-circuit cables 40W₁, 40W₂, 40R₁, and 40R₂are constituted as the flat flexible printed-circuit cable 40 shownFIGS. 16, 17, and 18, the flat flexible cables 40W₁, 40W₂, 40R₁, and40R₂ are exchangeable with each other due to the symmetrical arrangementas mentioned above. In particular, for example, when the flat flexiblecable 40W₁ as shown in FIG. 19 is turned over as indicated by arrow C,it successively takes attitudes as shown in FIGS. 20 and 21. Then, whenthe flat flexible cable 40W₁ as shown in FIG. 21 is rotated to anattitude as shown in FIG. 22, as indicated by arrow D (FIG. 21), it canbe used as the flat flexible cables 40W₂. Namely, the establishment ofelectrical connection between the magnetic head 26a and the amplifierprinted-circuit boards 26 and 26 can be carried out by using only onesort of flat flexible printed-circuit cables.

Finally, it will be understood by those skilled in the art that theforegoing description is of a preferred embodiment of the disclosedinvention, and that various changes and modifications may be made to thepresent invention without departing from the spirit and scope thereof.

We claim:
 1. A magnetic tape drive for a magnetic tape cartridge,comprising:a magnetic head unit having a magnetic head for writing dataon and reading data from a magnetic tape wound out of said cartridge; adata write amplifier printed-circuit board and a data read amplifierprinted-circuit board spaced from said magnetic head unit, each of saidwrite and read amplifier printed-circuit boards having a first connectorelement; two relay printed-circuit boards supported by said magnetichead unit, each of said relay printed-circuit boards having a secondconnector element, said second connector element being electricallyconnected to the magnetic head; two flat flexible printed-circuit cablesextending between said relay printed-circuit boards and said write andread amplifier printed-circuit boards, respectively, without requiringtwisting or folding of said flat flexible cables; and each of said flatflexible printed-circuit cables having first and second parallelsurfaces, first and second opposing ends, a third connector elementdisposed on said first surface at said first end, a fourth connectorelement disposed on said second surface at said second end, and acircuit patterns electrically connecting said third and fourth connectorelements together, said circuit pattern including a first portionextending on said first surface from said third connector element, and asecond portion extending on the second surface from said fourthconnector element, said first and second portions being electricallyconnected to each other via a connecting portion passing through athrough-hole defined in said each of said flexible printed circuitcables, said third connector element being connected to said firstconnector element, said fourth connector element being connected to saidsecond connector element.
 2. A magnetic tape drive as set forth in claim1, wherein said first and second opposing surfaces are symmetricallyshaped with respect to a geometrical center thereof, and said third andfourth connector elements are symmetrically disposed on said first andsecond ends with respect to said geometrical center.
 3. A magnetic tapedrive as set forth in claim 2, wherein said flat flexibleprinted-circuit cables are generally bent at an angle of about 90degrees such that said flat flexible printed-circuit cables initiallyextend from said amplifier printed-circuit boards to said two relayprinted-circuit boards, and then extend generally parallel to said tworelay printed-circuit boards.
 4. A magnetic tape drive as set forth inclaim 2, further comprising a hub having a radial slot formed thereinfor receiving a leader block of said magnetic tape threaded through saidmagnetic head.
 5. A magnetic tape drive as set forth in claim 4, whereinsaid hub is in spaced relationship with said magnetic head and alocation where the magnetic tape cartridge is loaded into the magnetictape drive.
 6. A magnetic tape drive as set forth in claim 5, whereinthe magnetic tape cartridge is a single-reel type magnetic tapecartridge.
 7. A magnetic tape drive as set forth in claim 1, whereinsaid flat flexible printed-circuit cables are generally bent at an angleof about 90 degrees such that said flat flexible printed-circuit cablesinitially extend from said amplifier printed-circuit boards to said tworelay printed-circuit boards, and then extend generally parallel to saidtwo relay printed-circuit boards.
 8. A magnetic tape drive as set forthin claim 7, wherein the magnetic tape cartridge is a single-reel typemagnetic tape cartridge.
 9. A magnetic tape drive as set forth in claim1, further comprising a hub having a radial slot formed therein forreceiving a leader block of said magnetic tape threaded through saidmagnetic head.
 10. A magnetic tape drive as set forth in claim 9,wherein said hub is in spaced relationship with said magnetic headcircuit boards and a location where the magnetic tape cartridge isloaded into the magnetic tape drive.